Media regulator Ofcom has effectively dismissed Channel 4's concerns about a rival bid from National Grid Wireless for the second national digital radio multiplex bid, saying all applications were judged on formats, not service providers.

In its bid for the licence submitted yesterday, NGW allocated two of its proposed 12-station lineup to Channel 4 radio services.

Channel 4 - which submitted its own proposal - said that it did not "recognise" the two Channel 4 radio stations described by NGW and raised the question of whether its rival could deliver the station formats it proposed to Ofcom.

However, in response, Ofcom said: "There is no requirement upon applicants for a national radio multiplex licence to identify providers of proposed services within their applications.

"All radio multiplex licensees are bound by the formats, which set out the type of programming services will provide, which they propose in their applications."

This means that if NGW won the licence and Channel 4 either refused, or was unable, to launch radio stations on the rival service, then other partners could be brought on board.

If its bid was successful, NGW would be held to delivering two stations based on the format description it filed in its bid application - one for a music-based general entertainment service, the other a talk-based station designed to appeal to "younger BBC Radio 4 listeners".

NGW maintains that if it is triumphant - Ofcom's Radio Licensing Committee is expected to make a decision by July - then Channel 4 will be given the "first refusal" to create the two digital stations.

"We can confirm that we have not held discussions with Channel 4 about providing any stations or content to us for our bid," said Tony Moretta, the general manager for broadcasting at National Grid Wireless and leader of its bid.

"We aren't saying any differently in our bid. We recognise that Channel 4 potentially have a role to play in digital. What we are saying is that, if we won, we believe they could still come with very good commercial radio stations because of their content and demographic."

Regardless of the offer, it is understood that there are financial questions over whether Channel 4 would be able to launch digital radio stations - it has proposed three of its own in its licence proposal - without winning the bid.

The development of the three Channel 4-branded radio stations is thought to be based on funding made available via the likes of carriage fees accrued from other companies in its 10-station lineup.

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